The Future for Satellite Technology

Although traditional VSAT technology, with its minimal uplink bandwidth, is not appropriate for some organizations, the newer systems in development should be reviewed by network architects. For example, Hughes' new system under development, the Spaceway system, is expected to provide a variety of low-cost broadband services with small satellite dishes, with data rates ranging from 512 kbps upstream and up to 30 Mbps downstream. Applications will include Internet access (with a strong multimedia component) to LAN/ WAN solutions for work-at-home employees, SOHOs, and large organizations.

Hughes' system includes full mesh point-to-point and multicast communications architecture. This allows the development of high bandwidth peer-to-peer applications, such as file sharing, distributed databases, and decentralized content distribution.

The availability of reasonably fast Internet links in rural areas around the world could significantly change the business dynamic of many firms. While the media continually laments the lack of bandwidth, the most serious deficiency of the Internet is actually the lack of geographic coverage.

Another alternative architecture is a hybrid system that uses satellite transmissions for downlink and terrestrial for uplink (currently used to provide Internet access to areas with no other broadband availability). Because satellites are large (many tons), they have power plants that allow megabit-per-second downloads of video, software upgrades, and other information. The terrestrial link in this asymmetric data access scheme provides for less latency (delay) for the user response. Most applications, as is the case with home Internet users, consume far more download bandwidth than upload bandwidth.

The technology of caching will be increasingly used for Internet services. Caching takes recently retrieved information, copies it, and places it on a server close to the consumer. This process allows users to access popular Internet data quickly because it is physically located much closer to the user. The more users are associated with a cache, the more the benefit because there will be a higher likelihood that a requested file will be in the cache. This could potentially speed the deployment of international intranets for global organizations. Caching is relevant to satellite transmissions because it reduces demand for repetitive uplinks from the hub for frequently used pages.

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